Performance of an actual engine compression release brakes can deviate from performance of a nominal engine compression release brake for a number of reasons, including machining tolerances of engine compression release brake components. This deviance from expected behavior can vary depending upon engine operating condition. For instance, an engine compression release brake might provide more load than expected at a low engine speed but less load than expected at a higher engine speed. Further, this engine compression release brake performance can change over its useable life, such as after it has been broken in.
In addition to influencing engine operation when utilized to provide engine braking, engine compression release brake performance deviations can affect performance of other engine components, either directly or indirectly, as well. For instance, if the engine compression release brakes are being utilized to provide a load in a performance test for one or more engine components, such as a fuel injector, the deviation of the actual performance of the engine compression release brake from its expected performance can influence the results of these tests.
One prior method of compensating for variability of engine components, such as engine compression release brakes, is disclosed in U.S. Pat. No. 5,634,448 to Shinogle et al. entitled Method and Structure for Controlling an Apparatus, such as a Fuel Injector, Using Electronic Trimming and issued on Jun. 3, 1997. This method reduces the effects of variability introduced by the manufacturing and assembly process of an apparatus, such as an engine compression release brake or a fuel injector, by adjusting a base signal for each engine brake and/or injector. After applying what is usually a unique adjustment to each engine brake, they perform more uniformly.
The present invention is directed to overcoming one or more of the problems as set forth above.